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bigben8686
02-09-2009, 08:17 PM
One day the car started sputtering and died, after that it would turn over and rarely start for a few seconds. I replaced the fuel pump and am getting fuel up to the pressure regulator on the rail but from there on you get nothing. No fuel to the injectors and nothing out of the return line. Please Help!

whiskychaser
02-10-2009, 04:11 AM
One day the car started sputtering and died, after that it would turn over and rarely start for a few seconds. I replaced the fuel pump and am getting fuel up to the pressure regulator on the rail but from there on you get nothing. No fuel to the injectors and nothing out of the return line. Please Help!

The regulator is on the 'return' side ie after the injectors. Check what fuel pressure you are getting by jumpering the relay. It should be about 50psi. If it isnt try pinching the return hose. If it increases that could be a weak pump or regulator stuck. You might also read Bill R's recent post about fitting a fuel check valve

russiankid
02-10-2009, 04:13 PM
The regulator is on the 'return' side ie after the injectors. Check what fuel pressure you are getting by jumpering the relay. It should be about 50psi. If it isnt try pinching the return hose. If it increases that could be a weak pump or regulator stuck. You might also read Bill R's recent post about fitting a fuel check valve

This is one of the mistakes that I made. When I changed my fuel lines I mixed the feed and return up at the connection on the engine. I was ready to tear my head off because I could not find the issue. After switching the lines she fired right up.:p

bigben8686
02-10-2009, 06:27 PM
This is one of the mistakes that I made. When I changed my fuel lines I mixed the feed and return up at the connection on the engine. I was ready to tear my head off because I could not find the issue. After switching the lines she fired right up.:p

The regulator is before the injectors on this engine, and the pressure and return lines are hooked up right. Maybe i explained it unclearly. We installed a new pump and pressure regulator and are getting fuel from the pump all the way up to the regulator(i took the line off and fuel was pressurized and there was plenty of it). From the regulator forward there is nothing coming out. I did notice a small vacuum line attached to the underside of the intake manifold that runs to the regulator itself. Any ideas?

bigben8686
02-10-2009, 06:41 PM
The regulator is on the 'return' side ie after the injectors. Check what fuel pressure you are getting by jumpering the relay. It should be about 50psi. If it isnt try pinching the return hose. If it increases that could be a weak pump or regulator stuck. You might also read Bill R's recent post about fitting a fuel check valve

Oh one more thing, not trying to be smart but what would be the purpose of a fuel pressure regulator after the injectors?

Dave M
02-10-2009, 08:09 PM
The regulator is before the injectors on this engine, and the pressure and return lines are hooked up right. Maybe i explained it unclearly. We installed a new pump and pressure regulator and are getting fuel from the pump all the way up to the regulator(i took the line off and fuel was pressurized and there was plenty of it). From the regulator forward there is nothing coming out. I did notice a small vacuum line attached to the underside of the intake manifold that runs to the regulator itself. Any ideas?

1994 build date 525 auto:

Regulator is on the return side of fuel rail.

http://img.photobucket.com/albums/v11/dave_macisaac/5.png

Yes, its a vacuum line. No, I don't have any ideas, except ;) .................

As you are adamant that the regulator is on the supply end of the rail, maybe we should make sure you have your supply and return lines correct.

Dave

632 Regal
02-11-2009, 01:40 AM
makes sure the pressure is provided at the injectors incase of a regulator fail, the car should be able to limp to service.


Oh one more thing, not trying to be smart but what would be the purpose of a fuel pressure regulator after the injectors?

whiskychaser
02-11-2009, 04:33 AM
The regulator is before the injectors on this engine, and the pressure and return lines are hooked up right. Maybe i explained it unclearly. We installed a new pump and pressure regulator and are getting fuel from the pump all the way up to the regulator(i took the line off and fuel was pressurized and there was plenty of it). From the regulator forward there is nothing coming out. I did notice a small vacuum line attached to the underside of the intake manifold that runs to the regulator itself. Any ideas?
The small hose to the inlet manifold is there to reduce the fuel pressure to take into account the vacuum created by the engine when it is running. For every inch of mercury that air pressure is reduced, it will drop about half of one psi. The regulator is on the return side to ensure the correct pressure is in the rail where it needs to be - not in the pipe leading up to it. Dave's diagram shows the direction of flow - fuel should be arriving at pipe 12. HTH

Bill R.
02-11-2009, 09:23 AM
regulator is after the injectors so to speak, that keeps the entire rail and all the injectors pressurized and then any addition pressure returns through the fuel line closest to the regulator, the parts diagram has arrows on it indicating the direction of flow, This way you have the same pressure at each injector since the return is at the end with the regulator.






Oh one more thing, not trying to be smart but what would be the purpose of a fuel pressure regulator after the injectors?